The present invention relates to a signal processing device for processing a differential signal from a sensor and a corresponding control device.
Although the present invention is depicted below primarily in connection with sensors for electric machines, said invention is not limited thereto. The present invention can in fact be used in every system in which differential signals are evaluated.
Electric machines, e.g. electric motors, are used today in a variety of applications. For example, electric motors can be used as the driving motors in electric vehicles.
In order to control such electric machines, it is necessary to know the position, respectively the position of the rotor of such an electric machine. In order to acquire the position of the rotor, position sensors, such as, e.g., resolvers can, for example, be used. The output signals of these position sensors can then, e.g., be evaluated by a microcontroller and thereby the position of the rotor of the electric machine can be determined.
Depending on the application, it is required that the signals of the position sensor lie in all relevant operating conditions within the input parameters of the microcontroller. It is furthermore frequently required that the information necessary for a diagnosis be acquired in the case of a fault.
The European patent publication EP 2 837 915 A1 shows a motor control having a corresponding resolver monitoring.